The long terms objectives of the research program are to investigate ways in which motivation influences the processes of social judgment and relevant aspects of social interaction. The more specific aim of the proposed research is to study a particular motivation, the need for cognitive closure, as it affects major cognitive and social phenomena. A range of antecedent condition and consequences of the need for closure will be investigated in reference to the following questions: I. How persons' degree of the need for closure influences the degree to which their judgment of a social target are based on pre-existing conceptions or stereotypes (i.e., are "theory driven") versus on the case information at hand (i.e. are "data driven"). II. How information in terms of momentarily or chronically accessible constructs III. How the need for closure affects persons' tendency to level causal attribution at the salient portion of the social stimulus field. IV. How the need for closure experienced by group members affects their reactions to opinion deviants. V. How differences in the need for closure among disagreeing members of a group affect their relative persuasiveness. All of the foregoing issues bear on major cognitive biases the understanding of which may have important health consequences both for improving the efficacy of health education through the overcoming of close mindedness and selective information processing, and for facilitating the modification of dysfunctional belief systems in the course of therapy. Altogether sixteen experimental studies are theoretical notions through use of heterogenous operational definitions of the need for closure.